《植物生理学报》 2018, 54(1): 133-144

木薯叶片响应干旱胁迫的磷酸化蛋白质组差异分析

常丽丽, 王力敏, 郭安平, 杨倩, 王旭初^*

中国热带农业科学院热带生物技术研究所, 海口571101

通信作者：王旭初；E-mail: xchwanghainan@163.com

摘　要：

本文以抗旱性较强的‘华南8号’木薯(Manihot esculenta)为材料, 分析正常供水、轻度干旱(干旱处理5 d)和重度干旱(干旱处理15 d)胁迫对木薯植株形态及叶片磷酸化蛋白质组的影响。结果表明, 随着干旱胁迫程度的增加, 木薯叶片从底部开始萎蔫、脱落, 但顶端叶片优先保持正常生长。干旱胁迫处理后, 共有28个磷酸化蛋白点在叶片中的表达丰度发生了显著变化。质谱(MS)鉴定显示, 这些蛋白质主要参与光合作用、能量代谢、碳代谢、胁迫与防御、结合和转录翻译等代谢途径。其中, 大部分参与光合作用的蛋白积累量在干旱胁迫后显著降低, 而参与能量代谢、碳代谢、胁迫与防御、转录翻译等途径的大部分蛋白质积累量则明显升高。由此推测, 木薯应答干旱胁迫可能是通过改变植株形态, 抑制叶片中的光合作用相关蛋白, 调控叶片碳分配过程, 同时, 通过有效清除活性氧, 防御氧化胁迫损伤, 防止蛋白变性和降解等方式。

关键词：木薯; 磷酸化蛋白质组; 干旱胁迫; 功能分类; 差异表达蛋白

收稿：2017-08-03   修定：2017-12-25

资助：国家自然科学基金项目(31400217)和中国热带农业科学院基本科研业务费专项资金项目(1630052017008)。

Differential phosphoproteomics of cassava leaves under drought stress

CHANG Li-Li, WANG Li-Min, GUO An-Ping, YANG Qian, WANG Xu-Chu^*

Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China

Corresponding author: WANG Xu-Chu; E-mail: xchwanghainan@163.com

Abstract:

Morphological and phosphoproteomic changes in leaves of the drought-tolerant cassava species (Manihot esculenta cv. SC8) were compared after the plants were subjected to the normal water application, mild drought treatment (5 d with drought) and severe drought stress (15 d with drought) conditions. Our results showed that cassava leaves could gradually wilt and shed from the bottom part of branches following the increased days of drought stress, but have a high priority to keep a normal growth in the top leaves. Furthermore, 28 drought-responsive phosphorylated proteins were positively identified by mass spectrometry (MS), representing 27 unique ones. These proteins were categorized into 7 main pathways, including photosynthesis, energy metabolism, carbon metabolism, defense and stress tolerance, protein binding related proteins, transcription and translation related proteins. Drought treatment decreased the accumulation of most proteins involving in photosynthesis, while the abundance of several proteins related to energy production, carbon metabolism, stress and defense, and transcriptional translation were up-regulated. Our results indicate that cassava can adapt the drought environment by changing its morphology, inhibiting the photosynthesis process, promoting the glycolysis pathway, regulating the carbon distribution process of cassava leaves, removing reactive oxygen species, preventing oxidative stress damage, as well as preventing protein denaturation and degradation.

Key words: cassava; phosphoproteomics; drought stress; functional classification; differentially expressed proteins